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                                                                   Exhibit 4.3.1

                             Aerovox Incorporated
                                      And
                   ChaseMellon Shareholder Services, L.L.C.
               (as successor rights agent to Mellon Bank, N.A.)
                                as Rights Agent

                            Amendment No. 1 to the
                               Rights Agreement
                         Dated as of December 1, 1989

Amendment No. 1

         This Amendment No. 1, dated as of October 7, 1999 (this "Amendment"),
                                                                  ---------
is among Aerovox Incorporated, a Delaware corporation (the "Company"), and
                                                            -------
ChaseMellon Shareholder Services, L.L.C. (as successor rights agent to Mellon
Bank, N.A.), as Rights Agent:

         WHEREAS, pursuant to Section 27 of the Rights Agreement (as defined
below), the Company may from time to time supplement or amend the Rights
Agreement in accordance with the provisions of Section 27 thereof;

         WHEREAS, pursuant to Section 27 of the Rights Agreement, the Rights
Agent shall join with the company in the execution and delivery of any
supplement or amendment;

         WHEREAS, the Company desires to make certain amendments to the Rights
Agreement; and

         WHEREAS, the execution and delivery of the Amendment by the Company and
the Rights Agent have been in all respects duly authorized by each of them;

         Accordingly, in consideration of the premises and the mutual agreements
herein set forth, the parties hereby agree as follows:

     Rights Agreement: Definitions.  This Amendment amends the Rights
     ------------------------------
              Agreement (as in effect prior to giving effect to this Amendment,
              the "Rights Agreement"). Terms defined in the Rights Agreement as
                   ----------------
              amended hereby (the "Amended Rights Agreement") and not otherwise
                                   ------------------------
              defined herein are used with the meaning so defined.

     Amendment of Rights Agreement.  Effective upon the date hereof, the Rights
     -----------------------------
              Agreement is amended as follows:

                    2.1. Amendment of Section 21. The term "$50 million" in
                         subsection (i) of Section 21 of the Rights Agreement is
                         hereby replaced by the term "$10 million."

         3.   General. This Amendment may be executed in any number of
              counterparts, which together shall constitute one instrument, and
              shall bind and inure to the benefit of the parties and their
              respective successors and assigns. This Amendment shall be

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              governed by and construed in accordance with the laws (other than
              the conflict of law rules) of The State of Delaware.

Each of the undersigned has caused this Amendment to be executed and delivered
by its duly authorized officer as an agreement under seal as of the date first
written above.

                                  AEROVOX INCORPORATED

                                  By:    Robert D. Elliott
                                  Title: President and Chief Executive Officer

                                  CHASEMELLON SHAREHOLDER SERVICES, L.L.C.
                                  (as successor rights agent to Mellon Bank,
                                  N.A.), as Rights Agent

                                  By:    Michael A. Nespoli
                                  Title: Vice President

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